Closure plug for containers



y 1948. E. M. AMESBURY EI'AL 2,445,465

CLOSURE PLUG FOR CONTAINERS Filed July 6, 1944 15 10 I7 INVENTORS.

EARL M.AMssauRY, THEODORE W.FRANKS BY 6, JOHN JESEVICH,JR.

ATTORNEY Patented July 20, 1948 CLOSURE PLUG FOR CONTAINERS Earl M.Amesbury, Theodore W. Franks, and John Jesevich, Jr., Chicago, Ill.,assignors to American Flange & Manufacturing (30., Inc., New York, N.Y., a corporation of Illinois Application July 6, 1944, Serial No.543,640

a claims. (Cl. 220-39) This invention relates to closure plugs forcontainers and particularly to those made complete- 1y out of one pieceof sheet metal.

The principal object of the invention is to provide closure plugs forcontainers from a minimum of material and with minimum effort.

Another object of the invention is to provide a complete closure plugout of one piece of sheet metal, which plug incorporates all of-thefeatures needed to satisfy trade requirements.

Another object of the invention is to provide a complete closure plugformed out of one piece of light weight sheet metal which isstrengthened by the forming of the single piece of material.

A further object of the invention is to provide closure plugs for largemetal containers, which closure plugs are made out of inexpensive, lightweight, material, are useable in standard container openings and areoperable with standard wrenching equipment. p

A still further object of the invention is to provide light weight sheetmetal plugs with integral, eflective, wrench engaging lugs.

Other and further objects of the invention will in part be obvious andwill in part appear as this description progresses andby reference tothe accompanying drawing.

With the development of a method and apparatus for forming substantiallystandard pipe threads in sheet metal, about the weight of the walls oflarge containers, such as steel barrels and drums, which developmentsare shown and described in the U. S. patent to Draper No. 2,145,587,some new possibilities opened up in the so called drum closure art. Oneof these wasthe possibility of using the corners of the square sheets,out of which the round heads for steel barrels and drums are stamped, inthe manufacture of closure plugs. Such material had heretofore beenconsidered as scrap.

In the past most plug threads, except those formed by die casting,needed to be out into the metal. This required heavier metal than thatobtained as drum scrap or its equivalent weight in new material toassure that the material remaining behind the threads would be at leastas thick as that of the container wall stock. Being made of suchsubstantially heavier material, these plugs could easily be providedwith a proper gasket seat and efiective wrench engaging means, whetherthe latter be integral with, or attached to, the plugs. Likewise, thewrench engaging means could be carried within the confines of the plugto enable it to be seated down within an opening and covered by acapseal.

When the attempt was made however, to employ metal of the weightnormally encountered in drum scrap, commonly running in the range of 14to 18 gauge steel sheet, in the making of effective one piece closureplugs, unforseen dimculties cropped up; particularly where theconservation of material and the forming of a flushtype plug werecontrolling factors. The plug head, if made as a mere extension ofvthebody as in the prior art, and made small enough to seat down flushwithin an opening, (as shown in U. S. patents to Shera. Nos. 1,982,144and 1,982,-

), was not strong enough. Its strength was insumcient to prevent theplug and its gasket seat from going out of round from the strains of"wrenching the plug. Furthermore, the head was not strong enough toprevent turning of the plug down into the opening past proper gasketingposition. In addition there was nothing rigid enough to carry effective,integral, wrench engaging means; thus a separate, supplemental bar orplate had to be secured to the plug wall in some way, involving separatematerial and operations. Obviously these defects and additions ofisetany advantages that might be derived from making such a plug out oflighter weight materials than had heretofore been the case.

We have however, devised a plug of the flush type which meets all therequirements of the trade, can be made out of light weight sheet metaland can be made all in one piece with a minimum expenditure of efiortand material. By first forming a cup shaped blank and thensimultaneously rolling threadsand swaging a gasket seat into thecylindrical wall of such cup we have been able to cause the metal of thecup to flow towards the free edge of the cup to such an extent as tosubstantially thicken it. This free edge carries upwardly extending earsto be formed into wrench engaging lugs. These ears are next given aright angle bend inward from a point about midway of their extent andare perforated adjacent their bases, all in one operation. Also, theyare bent inward and downward in another operation. 4

The perforation of the ears provides sealing Wire receiving eyelets butserves a more important purpose than that in facilitating the completionof the plug. Since the top of the plug is rim is swaged or coined intoits final form, the

perforations in the lugs are somewhat diminished in size. To completethe plug the lugs are further bent into the cup to bring their free endsback into engagement with the inside of the cup wall where it joins thebottom. The bead around such a plug is not a high one and the lugs liebelow the top of the head so the plug can be inserted in the common necktype of opening and be covered by a proper capseal. Finally, we havealso found that an additional thickening of the stock around the mouthof the plug can be achieved by the swaging or beading operation. Thisdoes its part toward strengthening the plug and making it a,commercially successful article.

The plug of the invention is satisfactory from all points of view. Itrequires no machining operations since the original blank is formed bystamping while the threads and gasket seat are rolled into the metal.The bead is formed by swaging and the lug positioning is completed byswaging and bending. The plug is made from one piece of inexpensivematerial yet, when finished, it meets all the requirements of the trade.

For a fuller understanding of the nature and objects of the inventionreference should be had to the following detailed description taken inconnection with the accompanying drawing in which: I

Fig. 1 is a plan view .of a closure plug of the invention.

Fig. 2 is an elevation of the same.

Fig. 3 is a section taken on line 3-3 of Fig. 1 looking in the directionof the arrows.

Fig. 4 is a section taken on line 44 of Fig. 1 looking in the directionof the arrows.

Fig. 5 is a perspective view of the plug looking down into the same.

Fig. 6 is a view partly in elevation and partly in section, showing aclosure .plug of the invention secured in place in a container wallopening properly formed to receive it and with a capseal secured inplace over the plug and the opening.

Fig. 7 is an enlarged fragmentary section of a portion of the screwthreaded wall, gasket seat, and reinforcing bead taken through thecenter of one of the wrench engaging lugs.

Fig. 8 is a similar view taken at a position I beyond the lug.

Throughout the several views of the drawing the closure plug of theinvention is generally indicated by the reference character 10. Thisclosure plug has a bottom wall II, and an upwardly extending side walll2 whose lower portion is threaded as shown at I3 and whose upperportion is inset as shown at H. The threads of the portion l3 are shownextending both externally and internally with respect to the normaloutline of the plug wall. This is due to their having been formeddirectly out of the stock of that wall by a roller swaging operationsuch as that disclomd in United States patent to Draper No. 2,145,587.The inset portion M, of the wall l2, provides an exterior seat, orsurface, l5, for the reception of a gasket l6. As shown best in Fig. '7,the inset I4 is of sufficient depth that the surface I5 is set back atleast as far as the roots of the externally extending threads. In thisway the gasket seat is bounded at its lower end by the uppermost threadand, at, its upper end by a laterally extending shoulder H.

The wall I2 terminates in a reinforcing bead or rim l8 overlying theshoulder l1 and materially strengthening the upper end of the plug. Thisstrengthening, as already described results from two steps in theformation of the plug. The first of these is the combination operationof rolling threads and gasket seat simultaneously which causes the metalto flow towards the part to be formed into the head or bead. The secondis the additional thickening achieved through the swaging of the stockextending above the surface I1 into beadlike form. This stock is thusnot only turned over on itself, inwardly, as shown at I9, but is at thesame time given an additional thickness with respect to the firstthickening tant of which is the imparting of rigidity to the plug as awhole. In the working of metal as done in forming and threading the plughere, internal stresses are set up which tend to cause distortion. Suchdistortion, though not necessarily of sufficient extent to preventadequate threaded engagement of the plug with the opening, neverthelesswould be of sufficient extent to impose an uneven pressure upon thegasket l6. In addition, the gasket might be permitted to creep oflf ofits seat at certain points in the circumference of that seat. Shouldeither .of these deleterious conditions exist it would be likely toprevent proper closing of the container wall opening. By the thickeningof the stock and the forming of the particular bead iii in the mannerdescribed however such distortion is substantially eliminated.

Another important function performed by the strengthened portion I8 isthe carrying of the wrench engaging lugs 20 which extend inwardly anddownwardly at 2| as an integral continuation of the inwardly turnedportion I9 01' the bead l8. These lugs extend into the hollow head ofthe plug a suflicient distance to enable their engagement by a simplewrench, bar, or the like and then are turned inwardly and downwardlyfrom their innermost extension 22 into substantial engagement with theinterior of the threaded wall at their termination at 23. Without athickened and reinforced bead to support and stiffen them, these lugswould readily collapse or tear when engaged by the normal type of wrenchor tool employed in this art. With the bead acting as it does however,and with the lugs turned inwardly at their bottoms to engage thethreaded wall, it has been found that they resist collapse and tearingto a marked extent. Thus the necessity of employing an additional partor parts secured to the plug to provide wrench engaging means isobviated.

Though this plug, as best shown in Fig. 6, is of the flush-type, i. e.,it seats down within the opening to which it is applied so that acapseal may be secured over it, there may be times when it is desirableto seal it in place by means of a lead and wire seal. As already pointedout, the perforation of lugs 20, to enable the material of the lugs toflow thereinto while the plug head and base of the lugs are being beadedover, is

most useful in eliminating distortion. These perforations should,however, be large enough so that after the lugs are fully formedperforations 24 are still large enough to enable a sealing wire to bepassed therethrough. Such wire, in accordance with common practice,would be anchored by means of the usual lug or eyelet carried on thecontainer wall.

The plug of this invention thus furnishes the solution to all theproblems which have heretofore prevented the use of light weight sheetmetal with swaged threads in the formation of economical flush-typeplugs. The strengthened, swaged bead around the head of the plugadequately strengthens it against distortion due to strains imposed uponit in the applying or removing of it. The complete plug is,nevertheless, all made out of one piece of material, so has theadvantage of economy of material and economy of forming operations,without sacrificing any of the requirements of the trade for aneffective plug.

In Fig. '7 there is shown a section taken through the middle of one ofthe wrench engaging lugs. From this showing it is apparent that the lugdoes not materially interfere with the forming of a uniform bead andgasket seat. Such would not be true however, were the perforations 24not made of substantial size at the outset to permit the flow of metalinto them. Instead a considerably distorted bead would result.

It is believed that changes and modifications could be made in thearticle above described without departing from the scope of theinvention and it is accordingly intended that the description anddrawing are to be interpreted merel as illustrative of the invention andnot in a limiting sense.

Having described our invention, what we claim is new and desire tosecure by Letters Patent is:

1. An integral one-piece sheet metal plug for containers, comprising, abottom portion, a side wall extending up therearound, said wall beingprovided with screw threads throughout a portion of its height, areinforcing bead around the free end of said wall, said bead beingformed by extending the stock of said wall outwardly and then turning itinwardly toterminate substantially in line with said side wall and atool engaging lug extending from the terminating edge of the inturnedportion to a point spaced from said 6 wardly from the inturned edge ofsaid bead and then reversed outwardly and downwardly to terminate inengagement with the interior of said wall.

4. An integral one-piece sheet metal plug for containers, comprising, abottom portion, a side wall extending up therearound in substantiallycylindrical form and a, re-inforcing bead around the open free end ofsaid cylindrical wall, said bead being formed by extending the stock ofsaid wall outwardly and then turning it inwardly to terminate in a freeedge and a tool engaging member extending from said free edge inwardlyof said plug and away from said adjacent side wall, said tool engagingmember extending a substantial distance away from the adjacent portionof said side wall and engaging the same again at a position spaced fromits commencement.

5. An integral'one-piece sheet metal plug for containers, comprising, abottom portion, a side wall extending up therearound in substantiallymember extending, from said free edge inwardly of said plug and awayfrom said adjacent. side wall, said tool engaging member extendingdownwardly throughout substantially the entire height of said side walland having a portion extending inwardly a substantial distance away fromthe opposed portion of said side wall.

6. An integral sheet metal closure plug for containers, comprising, abottom portion, a side wall extending up therearound in substantiallycylindrical form and a re-iniorcing bead around the open free end ofsaid cylindrical wall, said bead being formed by extending the stock ofsaid wall then turned backwardly to terminate in substantial engagementwith said wall.

2. In an integral one-piece sheet metal closure plug, the combination ofa side wall formed with roller swaged internally and externallyextending wall outwardly and then turning it inwardly to terminate in afree edge and a tool engaging member extending throughout substantiallythe entire height of said side wall, the upper end of said memberextending into said free edge at spaced positions and said tool engagingmember having an intermediate portion extending a substantlal distanceinwardly of said plug away substantially standard pipe threads, areturned bent, thickened, reinforcing bead formed around the end of saidscrew threaded wall and a wrench engaging lug extending integrally fromsaid bead away from said wall and returned into engagement with saidwall at a point spaced from said bead.

3. An integral one-piece flush type sheet metal closure plug forcontainers, comprising, a bottom disc-like portion, an annular side wallextending up around said disc-like portion and being provided,throughout a portion of its height with roller swaged substantiallstandard pipe threads, the stock of said wall above said threads beinginset with respect to the threaded portion to form a gasket receivingseat and the stock of said wall at the upper end of said gasket seatbeing formed outwardly and turned inwardly in the form of a bead, theportion of said stock comprising said bead being substantially thickerthan the adjacent stock to reinforce the open tending inwardly of andwithin the confines of said wall, said lugs extending inwardly anddownend end of said plug, and tool engaging lugs exfrom said side wall.

EARL M. AMESBURY. THEODORE W. FRANKS. JOHN-JESEVICH, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 640,121 Foreman Dec. 26, 1899874,256 Sleight Dec; 17, 1907 1,431,911 Jones Oct. 10, 1922 1,737,605Mauser Dec. 3, 1929 1,792,622 Wikstrom Feb. 17, 1931 1,838,285 RiekeDec. 29, 1931 2,254,005 Dodson Aug. 28, 1941 2,337,456 Draper Dec. 21,1943 FOREIGN PATENTS Number Country Date 177,084 Switzerland Aug. 1,1935 642,732 France May 6, 192B

